Multiscale Characterization of the Ultrastructure of Normal and Osteoporotic Human Trabecular Bone

Abstract

In this paper we characterized hierarchical structure of healthy and osteoporotic human trabecular bone from microscale down to nanoscale. To characterize the hierarchical structure, trabecular bone was investigated at the microstructural level (i.e. trabecula, trabecular packets), sub-microstructural level (lamellar structure) and the nanostructural level (crystal-collagen collagen composite). There was an emphasis on evaluating the sub-microstructure and nanostructure of trabecular bone since detailed descriptions of the lamellar structure and of the crystal-collagen relationship in osteoporotic bone are relatively unknown. The ultrastructure of healthy and osteoporotic human trabecular bone was characterized experimentally by means of transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The experiments also involved studying trabecular bone from C57BL/6J and C3H/HeJ mice. These mice have nearly the same size and weight, but have very different bone density. Thus, they were good candidates for a comparative study of healthy and osteoporotic human trabecular bone. TEM and SEM were used to characterize the hierarchical microstructure of trabecular bone in the inbred mice. The understanding of the hierarchical nature of healthy and osteoporotic bone microstructure is needed for a deeper understanding of the state of bone health and its mechanical properties.